MS, Registered Dietitian, Former President of CT Academy of Nutrition & Dietetics
How soon will you feel better after taking vitamin D? Learn how long it takes for vitamin D to improve your health & help you feel better.
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Many people take vitamin D supplements to improve their vitamin D levels or for more specific reasons like promoting bone health. Vitamin D is also responsible for reducing inflammation, providing immune health support, and more.
However, how long does it take for vitamin D to work?
In this article, we’ll discuss vitamin D deficiency, how long it takes to feel the effects of vitamin D supplements, and more.
Vitamin D, which is also known as calciferol, is an essential fat-soluble vitamin that is both found in food and can be produced from sun exposure. Many take vitamin D for fatigue, bone pain, muscle weakness, or to improve overall bone health.
Let’s talk about some factors that influence how long it takes to feel the effects of vitamin D supplementation when taken in appropriate doses.
There are two main factors determining how quickly you can resolve low vitamin D symptoms. These are the severity of the vitamin D deficiency and how low the vitamin D level was in the first place.
According to the National Institutes of Health (NIH), the measured lab values for vitamin D are as follows:
Additionally, the recommended dietary allowance (RDA) for adults aged 19 to 70 is 15 micrograms or 600 international units daily.
Cofactors are substances in the body that help enzymes work more effectively. More specifically, vitamin D cofactors help enzymes activate vitamin D so it can be properly used by the body.
Magnesium is the primary cofactor for vitamin D. [2] It works with calcium and phosphorus to promote bone health, including growth and maintenance.
Therefore, including a source of magnesium with your vitamin D is important for improving vitamin D levels.
Examples of good magnesium sources include nuts, beans, oatmeal, and avocado.
Vitamin D is a fat-soluble vitamin that plays a role in the body’s ability to absorb phosphorus and calcium, strengthening bones. [3]
It’s important to include a source of dietary fat alongside vitamin D— preferably a healthy fat, such as olive oil, avocado, nuts, or seeds, to help with its absorption.
Also, it is essential to include vitamin D sources in the diet, even when taking vitamin D.
Vitamin D is often fortified into dairy products, such as milk (including non-dairy milk alternatives) and yogurt, and also into drinks like orange juice and soy beverages. Additionally, you can naturally find vitamin D in sardines, salmon, egg yolks, and certain mushrooms.
Certain medications interact with vitamin D in the body, impairing the absorption and metabolism of vitamin D or vice versa. According to the NIH, these medications include steroids, statins, thiazide diuretics, or Orlistat. [1]
If you are taking any of these medications or are unsure if a different medication may be causing your vitamin D deficiency, speak with your physician for guidance.
Certain disease states can cause vitamin D malabsorption, whether relating to vitamin D itself or the fat it needs to be absorbed adequately.
According to the U.S. Department of Health and Human Services, these disease states can include Crohn’s disease, celiac disease, obesity, or those who have undergone gastric bypass surgery. [4] In these situations, speak with your physician and a registered dietitian nutritionist for individualized guidance.
In addition, for those that are obese, the body fat binds with some vitamin D in the body and prevents it from getting into the blood.
If you struggle to lose weight, a registered dietitian nutritionist can answer your questions (including some not-so-obvious ones) to help you lose weight.
Additionally, an all-in-one weight loss app can help simplify your weight loss tasks and provide accountability and support.
According to the American Society of Clinical Oncology, vitamin D supplementation was effective in treating vitamin D deficiency in a 12-week period. This resulted from one pilot study involving women who took high-dose vitamin D once a week for 12 weeks. [5]
However, as mentioned above, many factors that influence this time frame should be considered.
In another study, 95.7% of participants achieved normal serum vitamin D levels after only 5 weeks of therapy. [6]
It is not recommended to take too much vitamin D in hopes of speeding up the effects.
For adults, according to the NIH, the tolerable upper limit of vitamin D for male and female adults is 100 micrograms or 4,000 international units, or IUs. Therefore, make sure not to exceed this amount each day if not told otherwise by your healthcare provider. [1]
You will likely not immediately feel the effects of vitamin D supplementation. Give it time to begin to work in your body while continuing to consume vitamin D-rich foods in your diet.
Since vitamin D deficiency may cause symptoms including fatigue, body pains, and muscle weakness, you will likely feel improvements in these symptoms after taking vitamin D supplements and raising your blood levels.
How quickly does vitamin D work for fatigue? According to the journal Medicine, participants with vitamin D deficiency experienced an improvement in self-perceived fatigue after 30 days of taking a vitamin D supplement. [7]
Let’s summarize some key takeaways from this article.
This article is intended for general informational purposes only and does not address individual circumstances. It is not a substitute for professional advice or help and should not be relied on to make decisions of any kind. Any action you take upon the information presented in this article is strictly at your own risk and responsibility!